Answer:
the answer is 3
Step-by-step explanation:
(-5x-3)(-5x+3)=(5x)^2 - (3)^2
A difference of squares is the difference of two squared terms.
We have
a^2 - b^2
We can factorize the difference of squared terms like this:
a^2-b^2 = (a+b)(a-b)
We have (-5x-3)(-5x+3)
Lets prove it:
(-5x-3)(-5x+3) = (-5x*-5x)+(-5x*3)+(-3*-5x)+(-3*3)
(-5x-3)(-5x+3) = 25x^2+(-15x)+(15x)+(-9)
(-5x-3)(-5x+3) = 25x^2-15x+15x-9
(-5x-3)(-5x+3) = 25x^2-9
(-5x-3)(-5x+3) = (5x)^2 - (3)^2
Answer:
Step-by-step explanation:
The formula for determining confidence interval is expressed as
Confidence interval
= mean ± z × s/ √n
Where
z is the value of the z score
s = standard deviation
n = sample size
a) The 95% confidence level has a z value of 1.96
The 99% confidence level has a z value of 2.58
Since 99% confidence level z value is greater than 95% confidence level z value, if we input it into the formula, it will result to a higher confidence interval. So changing from a 95% confidence level to a 99% confidence level would make a confidence interval wider.
b) The √15 is smaller than the √350. This means that if we make use of the formula, √350 will give a lower confidence interval than that of √15. Therefore, the confidence interval would be narrower changing from a sample size of 15 to a sample size of 350.
c) Applying the formula, a standard deviation of 15 pounds would result to a lower confidence interval than a standard deviation of 20 pounds. Therefore, the confidence interval would be wider changing from a standard deviation of 15 pounds to a standard deviation of 20 pounds.
Answer:
B = (- 4,
)
Step-by-step explanation:
Using the Section formula
=
=
=
= - 4
=
=
=
= 
Thus coordinates of B = (- 4,
)
Answer:
X=10, x=4
Step-by-step explanation:
first, divide 14 by 2, and square it; giving you
x^2-14x+(7)^2=-40
Because 7^2 is 49, you have to add 49 to the other side; giving you
x^2-14x+(7)^2=9
Then factor the left side; giving you (x-7)^2=9
Take the square root of both sides, giving you
(x-7)^2= plus or minus 3
Then solve to get two solutions, 10 and 4